This week one of my tanks developed what looks like stringy/hair like algae through the tank.

I've just cleaned all my tanks out, 100% change in each, but just wondering, why didnt the other tanks develop it? I use the same stuff in each & they all get cleaned at the same time. & is there anything I can do/use to prevent it from possibly occuring again? Or is it just like regular algae?

I'm pretty sure I get this type of algae too. I like how it grows on my driftwood though, it stands straight up and waves in the gentle current. Mine is caused by 6500k light being on too long per day (and my tank is only 5g so it might be too concentrated)

All I can say is maybe you leave your lights on too long to. I am trying out a 8-10 hour day with the lights but its extremely hard with my unpredictable schedule. You could try a timer for your lights too.

As for controlling it, I keep live plants too and so I dose with a fert once or twice a week. Rub the algae off the front glass and let it grow everywhere else for the most part. Doesn't hurt anything but aesthetics. Plus,my nerite always has something to eat. :)

So its not harmful? Yeah it attatched itself to the thermometer in the tank & was floating horizontal. My boy seemed to enjoy swimming around in it but I'd never seen it before so I wasn't quite sure if it was a danger.

As long as you control it. It's light green right?? It's growing using photosynthesis, which is a process that also removes ammonia and nitrites (In VERY SMALL amounts, no need to reduce water changes). I like the natural look. Does it look like this:

I have had this problem for a while. I don't test my water though- if you have a test kit test yours and check for nitrates. I do weekly water changes and add seachem ferts I have some water bugs too which I read were signs of healthy water... Oh dear.

Around day 35 of my cycle, I started having algae and the tiny white worms, forgot the name. 0 ammonia & nitrite and 20-40 nitrate with lights on for 10 hrs.
I did not have a fish in there, but had 1 golden mystery snail, 4 Amanos, 8 baby RCS free roaming in the 5g planted tank.

I decided to turn off the lights every other day, after i did 50%WC, removed all the stringy grey hair color algae, stopped adding adding liquid ferts, and fed the invertebrates every other day. The situation corrected itself in a week.